When performing vehicle suspension alignment procedures, such as wheel camber adjustment, it is often necessary to adjust spacing between suspension components. For example, when setting camber on a McPherson strut-type suspension, typically the top anchor of the strut to knuckle assembly is loosened to allow movement of the strut, and the wheel is positioned as necessary by changing the position of the strut relative to the frame or knuckle assembly of the vehicle (i.e., by moving the top of the strut towards or away from the longitudinal center line of the vehicle). The top anchor is thereafter secured. When setting camber on a vehicle equipped with an upper wishbone arrangement other than with McPherson struts, the inner anchors of the wishbone are loosened, the wheel positioned as necessary by changing the location of the wishbone relative to the frame or inner body structure of the vehicle (i.e., by moving the wishbone towards or away from the longitudinal center line of the vehicle), and the inner anchors are thereafter secured.
Many vehicle suspension systems do not provide a mechanical means for positioning the wheel during the adjustment procedure, thus requiring manual application of force by the technician to the strut or wishbone to position the wheel. Since suspension adjustment procedures typically require the weight of the vehicle to be on the suspension during the procedure, such application of force can be problematic, depending on the weight of the vehicle and the location of the suspension members. This problem is especially acute if the vehicle is equipped with upper wishbones and "slot-type" adjustment holes for the wishbones.
A tool for moving a suspension member, especially a McPherson strut, to position a wheel is disclosed in U.S. Pat. No. 5,535,651 (Perez). Referring to FIGS. 1A and 1B, Perez teaches an expanding adjustment tool comprising a spreader plate 16 pivotally mounted to an engaging yoke 12, a handle 18 for facilitating placement of the tool between two members to be adjusted, and a crank-operated adjustment assembly 20 for pivoting spreader plate 16 relative to yoke 12. In use, spreader plate 16 engages the frame or inner body of the vehicle, and yoke 12 engages the strut while crank 30 is turned to move spreader plate 16 and yoke 12 apart to move the strut.
Disadvantageously, Perez' adjustment tool is not easily adaptable to perform adjustments on differently-configured vehicles. For example, although spreader plate 16 and yoke 12 are suitably sized for moving the strut on one vehicle, they may be too large or small, or incorrectly shaped, for moving the strut of a different vehicle; e.g., a vehicle produced by another manufacturer. In other words, if the tool is designed to fit a first vehicle, it may not fit between the components of another vehicle, may not bear properly against the components, or both. Similarly, crank 30 is inconvenient to operate on some vehicles due to space constraints, and handle 18 is not of the proper length for manipulation of the tool on some vehicles. Thus, a number of differently sized tools must be purchased and stored if alignment is to be performed on a variety of vehicles, increasing costs. Furthermore, Perez' adjustment tool is not suitable for performing adjustments on vehicles having upper wishbones instead of struts because yoke 12 does not fit between the wishbone and the vehicle frame or inner body.
There exists a need for an expanding adjustment tool for suspension alignment that is usable on a wide variety of vehicles, including vehicles equipped with McPherson struts or upper wishbones.